Determine if there is a dimension logical table on which these fields can be added.
If there is an existing dimension, add a new table source that maps to the fact table and then map the fields.
If there is no adequate logical table, complete the following steps:
Create a new logical table.
Create a table source that maps to the fact table.
Create a dimension hierarchy for this new logical table.
In the business model diagram, create a complex join between the dimension logical table and the fact logical table. Also create a complex join to any other fact logical table mapped to the same physical table.